Data from the 1997 cohort of the National Longitudinal Survey of Youth were used to assess the association between family, self, proximate extra-familial, and distal extra-familial system factors and abstinence/virginity and age of first sexual intercourse by ethnicity and race (N = 1,854). Findings show how and in what circumstances measures associated with these four factors vary for Black, White, and Hispanic youth. Findings point to the robustness of class and gender for each ethnic-racial group on timing of sexual initiation and of delinquency and negative peer relations on abstinence among Black and White youth and of religious affiliation among Hispanic youth. [ABSTRACT FROM AUTHOR]